Tree digging apparatus

ABSTRACT

An apparatus for continuous field digging and cleaning of nursery trees for transplanting comprises; a support frame pulled by a tractor with a fixed ground engagement digging blade and a pivoted removal and treatment basket extending therefrom. A powered eccentric drive arm secured to the basket oscillating same within a confined range of movement so as to expose and free the tree root system from the surrounding earth during operation.

This is a continuation in part patent application of Ser. No.08/991,576, filed Dec. 16, 1997, now pending.

BACKGROUND OF THE INVENTION

1. Technical Field

This device relates to tree digging equipment that is used to dig andremove small nursery grown trees for transplanting and sale. Suchdevices typically have a digging blade or blades that are engaged intothe ground by hydraulic means or pulled along behind a tractor like aplow.

2. Description of Prior Art

These types of devices typically have a variety of different removaltechniques in which sometimes the blade is oscillated as it digs and isconnected to a following basket that separates the tree roots from theearthen root ball as the tree is dug.

The problem associated with such prior art devices is two-fold, thefirst being the ability of the blade and attached basket assembly to digand separate the roots from the earth in efficient and continuousmanner.

Secondly, the nature of such devices imparts long term stress to thetractor due in part to the forces required by the oscillating blade asit engages the ground. Also many of such prior art devices use directpower take-offs from the tractor to drive the blade and basket whichbecomes an additional safety factor as well as additional maintenancerequired on the power take-off system, see U.S. Pat. Nos. 4,445,557,4,676,013, 4,305,213 and conventionally available diggers illustrated incatalog sheets and advertising pages manufactured by Egedal MaskinfabrikA/S, Exhibit A and such devices manufactured by Pioneer Metal Works ofQuincy, Washington, titled "Lil Digger", Exhibit B.

OBJECTS AND ADVANTAGES

Accordingly, it is an object of the present invention to provide acombination tree digging and root cleaning device that utilizes a fixeddigging blade on a dual support frame assembly with a pivoting shakerbasket extending therefrom that is oscillated by an onboard hydraulicmotor and cam assembly. The present invention is accordingly tractorfriendly with reduced stress imparted to the tractor while providingsuperior digging and root cleaning device that digs, guides andseparates the tree roots in one continuous self-contained action.

SUMMARY OF THE INVENTION

A tree digging device generally comprising; a support frame with a fixeddigging blade extending therefrom. A guide and root separation basketpivotally secured thereto. An oscillation device supporting the basketfor removal of dirt from the tree roots providing a self-containeddigging apparatus that is secured to a tractor.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevational view of the apparatus of the invention;

FIG. 2 is a top plan view of the invention;

FIG. 3 is an end elevational view of the invention;

FIG. 4 is an enlarged partial elevated view with portions broken awayfor clarity;

FIG. 5 is an enlarged sectional view of the oscillation cam assembly ofthe invention;

FIG. 6 is an enlarged side elevational view of the drive assembly withportions in sectional view;

FIG. 7 is a side elevational view of the invention in use behind atractor (not shown); and

FIG. 8 is a graphic illustration of the functional path of the treedigging device of the invention in use.

FIG. 9 is a front elevational view of an alternate form of the inventionhaving an overhead support frame;

FIG. 10 is a top plan view of the alternate form of the invention shownin FIG. 9; and

FIG. 11 is a side elevational view of the alternate form of theinvention shown in FIG. 9.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1, 2 and 3 of the drawings, a tree digging andseparation device can be seen having a main support frame 11 defining anattachment and a drive portion 12 and a blade support portion 13. Theattachment and drive portion 12 has a generally rectangular frame basewith outwardly extending front frame element 14 and a rear frame element15. The front and rear frame elements are interconnected by a pair ofoppositely disposed end frame elements 16 and 17 and intermediate frameelements 18 & 18A. A plurality of vertically upstanding frame elements19, 20 and 21 extend from said front frame element 14 corresponding tosaid hereinbefore described interconnecting elements 16 and 17. Asecondary front frame element 22 overlies the free ends of saidupstanding frame elements 19-21 with angularly positioned supportmembers 19A, 20A and 21A interconnecting the secondary front frameelement 22 with the respective interconnecting elements 16, 17 and 18Aas will be well understood by those skilled in the art.

An intermediate brace 23 extends between the front frame element 14 andthe secondary front frame element 22 from which extends a hitch bracket24. A pair of secondary hitch brackets 25 and 26 extend from and belowthe front frame element 14 in alignment with said respective upstandingfront elements 20 and 21 as best seen in FIGS. 1 and 2 of the drawingsdefining a typical three point hitch for engagement with a farm tractorother like device (not shown).

The blade support portion 13 extends from the attachment and driveportion 12 by extensions of the end frame element 16 at 27 and frontframe element 14 at 28. A cross support rear frame element 29 extends atright angles from said frame extension 27 interconnected to a secondaryend frame element 30 in spaced parallel relation thereto.

Wheel assemblies 30A are secured to the frame digging portion 13 on theends of the respective frame extension element 27 and the free end ofthe secondary end frame element 30 and to the attachment and driveportion 12 on the juncture of the end frame 17 between the rear frameelement 15 and front frame element 14. Each of the wheel assemblies 30Ahave a pair of apertured spaced parallel guide brackets 31 with aapertured wheel axle mounting element 32 movably positionedtherebetween. A release pin 33 extends through the aligned aperturedguide brackets 31 and intervening wheel axle mounting element 32adjustably securing same as will be well understood by those skilled inthe art. A wheel axle bearing assembly 34 extends from the axle mountingelement 32 with a wheel and tire assembly 35 thereon. As will bediscussed in greater detail by adjusting the wheel assemblies 30A thedetermination of the engagement depth of the digging device is achieved.

Referring now to the digging frame portion 13, a ground engagement blade36 extends between frame element extension 28 and the secondary endframe element 30 from respective mounting plates 28A and 30B. The blade36 is of a U-shaped transversely flat metal band configuration having aleading engagement edge 37A and a trailing edge 37B and correspondinglyextends well below the horizontal plane line PL of the front frameelement 14 as illustrated in broken lines in FIG. 1 of the drawings. Apair of oppositely disposed spaced parallel support arms 38 and 39extend from the digging frame portion 13 adjacent the blade mounts 28Aand 30B. Each of the support arms 38 and 39 have an adjustable diskmounting assembly 40 on their respective free ends to position andsupport a cutting disk 41 in forward alignment with the respective blademounting plates 28A and 30B. It will be evident from the abovedescription that as such cutting disks 41 engage the ground G in theblade path BP before the blade 36 cutting any ancillary vegetation, asbest seen in FIGS. 7 and 8 of the drawings.

The blade 36 itself has a slight angular offset to vertical, best seenin FIG. 7 of the drawings, to engage and lift the ground G within theconfines of the blade configuration in use. A retrieval and processingbasket 42 is positioned within the blade support portion 13 havinglongitudinally extending spaced parallel multiple support bars 43 and 44interconnected by transversely extending support rods 45 with anintermittent parallel bar 46 as best seen in FIG. 2 of the drawings. Apair of transition guide bars 47 are pivotally connected to therespective free ends of said support bars 43 and 44 and are affixed tothe trailing edge 37B of the blade 36. Each of the support bars 43 and44 have a pair of vertically spaced guide side rails 43A and 43B and 44Aand 44B respectively extending in spaced parallel relation therefrom bypairs of bar stubs 45 therebetween. Accordingly, the vertically spacedascending side rails 43A and 43B, 44A and 44B define an arcuateenclosure extending from the apex A of the blade 36 to a point that isabove the horizontal plane of the cross support rear frame element 29which is offset below the adjacent frame members 27-30 as best seen inFIG. 3 of the drawings.

The guide side rails 43B and 44B are angularly offset with the rails 44Aand 44B extending in angular offset spaced vertical relation therefrom.It will be further seen that the multiple support bars 43, 44 and 46 andrespective pairs of upstanding guide rails 43A and 43B and 44A and 44Bare angularly inclined at transition points 47 thereby changing theangular inclination of the basket 42 as it extends between the blade 36and the rear frame element 29 as hereinbefore described and best seen inFIG. 3 of the drawings.

The change in angular inclination at 47 is required due to the relativedepth of the digging blade 36 and the offset nature of the rear frameelement 29. This provides for ease of tree removal as will be describedin greater detail hereinafter.

Referring now to FIGS. 1-6 of the drawings, an oscillating driveassembly 48 can be seen secured to the attachment and drive portion 12along the rear frame element 15 between the front element 14 andintermediate frame element 18 on a support mounting plate 49. Theoscillation drive assembly 48 comprises a hydraulic motor 50 with achain driven drive shaft 51. A pair of bearing blocks 52 and 53 supportthe drive shaft 51 on the main support frame. An eccentric cam assembly54 is mounted on the free end of the drive shaft 51 having a cam block55 on the drive shaft 51 on which is positioned a crank housing 56 by apair of oppositely disposed tapered roller bearings 57, best seen inFIG. 6 of the drawings. The crank housing 56 has respective end caps 56Aand 56B to provide a seal for the assembly.

A crank arm 58 extends integrally from the housing 56 with an extensionportion that terminates in a basket mounting block 59 below thehereinbefore described basket 42, best seen in FIG. 4 of the drawings.The mounting block 59 has apertured lugs 60 aligned with respectiveapertured basket mounting tabs 61 with registerable fasteners F thatextend therethrough.

It will be evident from the above description that as the drive shaft 51rotates, the cam block 55 will oscillate the crank housing 56 andattached crank arm 58, thus imparting a rapid shaking motion to theattached basket 42 that pivots from the blade 36 as hereinbeforedescribed.

Referring now to FIG. 7 of the drawings, the tree digging device of theinvention can be seen in operation to be pulled by a mechanized farmmachinery, not shown, indicated by directional arrow at 62. As thedigging device of the invention moves forward the blade 36 is engaged inthe ground G to a depth determined by the adjustable wheel assemblies30. The blade 36 extends below and to the respective sides of a nurserytree T-1 shown in broken lines and about the tree roots T-R. As thedigger progresses a root ball is formed about the tree illustrated atT-2 beyond the trailing edge 37B of the blade 36 within the verticallyoscillating basket 42. As the tree and its root ball is advanced in thebasket by the next tree the dirt is removed from the root ball by theshaking and sifting action imparted thereto by the basket 42 byinterconnected oscillation drive assembly 48 delivering a bare root treeillustrated at T-3 for removal at the opposite end of the basket 42adjacent the rear frame element 29.

Thus it will be seen that during use that the change in angularinclination at 47 and angular side rails 43AB and 44AB are critical tomaintain the tree within the basket 42 and remove the dirt about theroot ball RB by the sifting action of the basket cleanly separating thetree roots from the sole without any additional cleaning of the treeroots heretofore required. It will also be apparent that by supportingthe blade 36 at the mounting plate 30A on the secondary end frameelement 30 will assure that the blade 36 is stable by transferring theimparted load force of the ground G back through the cross support rearframe element 29 to the main support frame characterized by theattachment and drive portion 12 as hereinbefore described.

Referring back to FIGS. 1 and 2 of the drawings, it will be seen that asthe front frame element 14 extends beyond the intersection of the endframe element 17 it defines an extension element 65 having an adjustablecounter weight assembly 66 on its free end thereof. The counter weightassembly 66 is of a type typically found on farm tractors with amounting bracket 67 having and a plurality of removably positionedcounter weights 68 within. The counter weight is used to co-balance outthe support frame of the invention offsetting the weight of the diggingportion 13 as hereinbefore described. An outboard ground engagement arm69 extends from the assembly 66 at a 90 degree angle to said front frameelement 65. The ground engagement arm 69 has an ground engaging shoe 70on its free end with the arm 69 and ground engaging shoe 70 providing across-counter ground anchor to offset the implicit torsional torqueimparted to the tree digging device as the blade 36 and attachedoscillating basket 42 is pulled through the ground G during the diggingprocess. The ground engagement arm 69 resist the digging device of theinvention's tendency to twist under the hereinbefore described loads.

Referring now to FIGS. 9, 10, and 11 of the drawings, a tree digging andseparating device 70 can be seen having a main support frame 71 definingan attachment and drive portion 72 and a blade support portion 73. Theattachment and drive portion 72 has a generally rectangular frame basewithout extending front frame element 74 and a rear frame element 75. Apair of secondary hitch brackets 76 and 77 extend from and below thefront frame element 74 defining a typical three point hitch forengagement with a farm tractor or other like devices (not shown).

The blade support portion 73 extends from the attachment and driveportion 72 by extension of an overhead frame 78, having a pair ofoppositely disposed parallel upstanding frame elements 79 and 80interconnected by a cross frame element 81 and interior support gussesat 82 respectively. An angled support frame element 83 extends from thecross frame element 81 back to main frame 71. Frame element extensions84 and 85 extend from the upstanding frame element 79 and front frameelement 74.

Wheel assembles WS are secured to the frame at multiple locations whichwill be well understood by those skilled in the art and as hereinbeforedescribed in the primary form of the invention.

A ground engagement blade 86 extends between frame element extension 84and 85 from their respective mounting plates 87 and 88. The blade 86 isof a U-shaped transversely flat metal band configuration having a slightangular offset to vertical to engage and lift the ground G within theconfines of the blade configuration in use. A retrieval and processingbasket 89 extends from the blade 86 as hereinbefore described with anoscillating drive assembly 90 that is secured through the attachment anddrive portion 72 along the rear frame element 75. The oscillating driveassembly has an eccentric cam assembly 91 interconnected to the basket89 for oscillation thereof during use.

Referring now to FIG. 11 of the drawings, the alternate digging andseparation device 70 of the invention can be seen in operation to bepulled by a mechanized farm machinery, not shown, indicated by thedirectional arrow at 92. As the digging device of the invention movesforward the blade 86 is engaged in the ground G to a depth determined bythe adjustable wheel assemblies WS. The blade 86 extends below and tothe respective sides of a nursery tree T-1 shown in broken lines andabout the tree roots T-R. As the digger progresses a root ball is formedabout the tree illustrated at T-2 within the vertical oscillating basket89. As the tree and its root ball is advanced in the basket 89 by thenext tree, the dirt is removed from the root ball by shaking andshifting action imparted thereto by the basket 89 by the interconnectingoscillating drive assembly 90 delivering a bare root tree illustrated atT-3 for removal at the opposite end of the basket 76.

The alternate form of the tree digging and stacking device 70 of theinvention provides the overhead frame 78 assembly to support the diggingblade 86 while allowing clearance for trees T-1 to pass thereunder.

It will thus be seen that a new and novel tree digging device fornursery trees has been illustrated and described and it will be apparentto those skilled in the art that various changes and modifications maybe made therein without departing from the spirit of the invention.

Therefore I claim:
 1. A tree digging device for use in continuouslyremoving a row of trees from the ground comprising; a main supportframe, a blade support portion extending therefrom, a U-shaped bladesecured within said blade support portion and extending therebeyond soas to be engageable into and through the ground under the row of trees,a separation basket extending from said blade, means on said bladesupport portion for engaging the ground in spaced alignment with saidblade, said blade support portion extending in spaced vertical relationto said U-shaped blade, means for oscillating said separation basketindependently from said blade and said main support frame and said bladesupport portion, means for adjustably positioning said main supportframe and blade support portion in spaced vertical relation to theground, means on said main support frame for removably securing saidmain support frame to a self-powered pulling vehicle.
 2. The treedigging device set forth in claim 1 wherein said main support frame hasan attachment and drive portion.
 3. The tree digging device set forth inclaim 1 wherein said separation basket comprises; multiple support barspivotally extending from transition guide bars secured to said U-shapedblade, pairs of guide side rails extending vertically from said multiplesupport bars in angular relation thereto.
 4. The tree digging device setforth in claim 1 wherein said means for oscillating said basketcomprises; a cam block rotatably positioned on a drive shaft, a crankarm extending from said cam block and secured to said separation basket,a drive motor in communication with said drive shaft and a source ofpower for said drive motor.
 5. The tree digging device set forth inclaim 1 further comprises an extension element on said main supportframe, an adjustable weight on the end of said extension element.
 6. Thetree digging device set forth in claim 1 wherein said means foradjustably positioning said main support frame in spaced verticalrelation with said ground comprises; multiple wheel assemblies.
 7. Thetree digging device set forth in claim 6 wherein said wheel assembliescomprises apertured guide brackets, a wheel support arm adjustablypositioned between said brackets, an axle bearing and wheel assembly onsaid wheel support arm and a tire on said wheel assembly.
 8. The treedigging device set forth in claim 1 wherein said means on said mainsupport frame for removably securing said main support frame to aself-powered pulling vehicle comprises; a three point hitch on mainsupport frame.
 9. The tree digging device set forth in claim 1 whereinsaid U-shaped blade is fixed and angularly inclined from a vertical. 10.The tree digging device set forth in claim 1 wherein said blade supportportion comprises; a pair of spaced parallel upstanding frame elements,and an interconnecting frame element extending therebetween, and angularsupport elements extending therefrom to said main support frame.
 11. Thetree digging device set forth in claim 1 wherein said means on saidblade support portion for engaging the ground in spaced alignment withsaid blade comprises; a pair of ground engaging cutting disks.